At least for the European Central Bank, housing is the single largest item in the inflation basket - entered as something called "imputed rent" - how much would it cost to rent an equivalent dwelling. This item alone accounts for 7.5% of the overall index.

Adding housing maintenance, heating, water supply, etc. - the entire housing category climbs up to 17.8%. Which sounds like a totally reasonable estimate to me - young people and urbanites pay more, older folks and people in rural or provincial towns pay much less. From my personal experience - housing and related expenses were ~50% of my income while paying down mortgage, down to ~7% after the loan was repaid